Are you saving the files in .PSD format?
Have you tried updating Photoshop CC 2017.1.1?
yes to the .psd format and my cc 2017 is up to date, but still no luck
Is it happening with all the document or only one specific document?
Its happening with every file, i even tried restarting my computer
Could you check if only guides are disappearing or other settings are also reverting back?